Switched capacitor sample-and-hold circuit with input signal range beyond supply voltage

A switched capacitor sample-and-hold (S/H) circuit with extended dynamic range beyond the supply voltage is presented. The proposed architecture includes a gate-bootstrapped circuit and an improved flip-around S/H with two selectable configurations. Simulations in a 0.13 μm CMOS technology show that the new system is capable of sampling a below-ground signal and allows an interface adapter that enhances the dynamic range of the low-voltage analog-to-digital (A/D) converters without affecting the input bandwidth. © 2008 IEEE.